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1、表面改性纳米碳酸钙原位悬浮聚合PVC的制备与性能研究黄东; 甄卫军; 宋晓玲; 骆雁;采用湿法表面改性的纳米碳酸钙(nano-CaCO3)与VCM原位聚合,制备了nano-CaCO3原位聚合PVC树脂(简称原位PVC树脂),研究了其力学性能、加工性能、微观形貌和热稳定性等。结果表明:nano-CaCO3能够很好地分散在PVC树脂中,对PVC基体产生很好的补强作用;与普通PVC试样相比,原位PVC试样缺口冲击强度提高到13.3 kJ/m2,效果显著;其加工性能也得到了提高。试样冲击断面的扫描电子显微镜照片表明原位PVC试样为韧性断裂,普通PVC试样为脆性断裂。DSC试验表明,原位PVC树脂的热稳

2、定性优于纯PVC树脂。聚氯乙烯 2010.07纳米级CaCO_3对聚氯乙烯/丙烯酸酯橡胶的增韧改性吴立波; 华幼卿; 黄玉强;采用丙烯酸酯橡胶 (ACR)、纳米级CaCO3 对聚氯乙烯 (PVC)进行增韧改性 ,并对该体系的断裂面形貌和加工流变性能进行了研究。结果表明 ,纳米级CaCO3 能进一步改善PVC/ACR共混合金的冲击性能 ;其加工流变性能不仅没有降低 ,而且略有提高北京化工大学学报2001.02无机纳米粒子改性PVC研究进展刘小强; 闫军; 杜仕国;综述了纳米CaCO3 、纳米SiO2 等无机纳米粒子在PVC改性中应用的最新研究进展 ,并指出了有待于深入研究的几个问题塑料科技 20

3、05.01高强度聚氯乙烯共混材料研制胡圣飞; 彭少贤; 应继儒; 杜志云研究了聚氯乙烯(PVC)与SBS的相容性,重点探讨了纳米级CaCO_3与轻质CaCO_3对PVC/SBS共混体系的影响。工程塑料应用2000.02聚氯乙烯纳米塑料研究进展王成云; 张伟亚; 杨左军; 魏东;介绍了共混法及原位聚合法两种PVC纳米塑料的制备方法 ,概述了PVC纳米塑料的研究进展情况 ,主要介绍了纳米SiO2 和纳米CaCO3 两种PVC中常用的纳米无机填料及其在各种PVC中的填充效果。指出目前聚氯乙烯纳米塑料的研究、开发和应用还处于起步阶段 ,有待于研究的理论和实际问题还很多 ,但作为一种重要的新型材料 ,其

4、应用必将具有广阔的前景聚氯乙烯2001.06刚性有机填料同时增韧增强改性硬PVC韧性体的研究吴其晔; 杨文君; 裘怿明;正 刚性有机填料(简称ROF)是用作塑料改性剂的刚性有机聚合物,如PS、PMMA、SAN等。实验发现将少许ROF填充到硬聚氯乙烯韧性体中,能使基体的冲击强度和拉伸强度同时提高,获得既增韧又增强的双重效果。克服了传统的弹性体增韧改性损害基体强度的缺陷。高等化学学报1993.03Functionalization of Multi-Walled Carbon Nanotubes by Stereoselective Nucleophilic Substitution on PVC

5、Horacio J. Salavagione*, Gerardo Martnez, and Carmen Ballesteros Macromolecules, 2010, 43 (23), pp 97549760In this article, multiwalled carbon nanotubes (MWNT) soluble in common organic solvents are prepared. The solubility is conferred to the MWNTs by covalent attaching of appropriately modified po

6、ly(vinyl chloride)(PVC). The nucleophilic substitution of PVC with potassium 4-hydroxythiophenolate is carefully studied. It proceeds through a stereoselective mechanism. The subsequent esterification reaction of the hydroxyl pendant groups in the modified PVC (mPVC) with carboxylic acids created in

7、 MWNT is reported. The intermediates and final products are characterized by FTIR, 1H and 13C NMR, and Raman spectroscopy. The thermal stability as well as the molecular dynamics of the MWNT-modified PVC (MWNT-mPVC) are studied. The potential applications of the PVC-functionalized carbon nanotubes a

8、nd the demonstrated functionalization strategy are discussed.The Gas Transport Properties of PVC Functionalized with Mercapto Pyridine GroupsP. Tiemblo,* J. Guzmn, E. Riande, C. Mijangos, and H. ReineckeMacromolecules, 2002, 35 (2), pp 420424The diffusivity, permeability, and solubility coefficients

9、 of O2, N2, CO2, and CH4 have been measured in PVC and in four samples of PVC functionalized with mercapto pyridine groups up to 6.8, 11, 21, and 46 mol %. It has been found that the permeability of all four gases progressively increases by a factor of more than 4 because of a similar increase in th

10、e diffusion coefficients. In addition, permeability selectivity augments significantly for the gas pair O2/N2 and only slightly for the pair CO2/CH4. The structural changes in the modified samples have been monitored by means of density and Tg determinations and FFV calculations, which are a measure

11、 of interchain spacing and chain stiffness. An interpretation of the changes seen in the gas transport properties of modified PVC samples has been proposed in terms of the structural changes introduced by the progressive functionalization of the PVC chains. Gas transport in fluorothiophenyl modified

12、 PVC membranes Karina Bierbrauera, b, Mar Lpez-Gonzlezb, , , Evaristo Riandeb and Carmen MijangosbThis work reports the modification of poly(vinyl chloride) by partially replacing the chlorine atoms of the chains with moieties derived from fluorinated nucleophilic compounds: 4-fluorothiophenol, 3,4-

13、difluorothiophenol and pentafluorothiophenol. Membranes were cast from tetrahydrofuran solutions of the modified poly(vinyl chloride)s and the permeability and diffusion coefficients of hydrogen, nitrogen, oxygen, carbon dioxide and methane through the membranes were measured using permeation techni

14、ques. The influence of both the degree of modification and the number of fluorine atoms containing in functionalizing groups on the performance of the membranes was thoroughly investigated. A permselectivity study is also presented in order to evaluate the potential applicability of the membranes fo

15、r gases separationImportance of Covalent Linkages in the Preparation of Effective Reduced Graphene OxidePoly(vinyl chloride) NanocompositesHoracio J. Salavagione* and Gerardo Martnez Macromolecules, 2011, 44 (8), pp 26852692The preparation of nanocomposites of reduced graphene oxide (RGO) with poly(

16、vinyl chloride) (PVC) is reported. Covalent modification of PVC with RGO and reduction/precipitation of graphite oxide and isocyanates-modified GO in the presence of PVC are studied. Among these methods it is proposed that only the former produces nanocomposites with enhanced final properties. The o

17、ther method failed because it did not produce nanocomposites with different properties to the original polymer, probably due to the lack of effective interfacial interactions. The RGO-chemically modified PVC samples have different thermal and mechanical properties with respect to the parent polymer.

18、 A discussion on the dependence of the properties on the method of preparation is given. Furthermore, preliminary results based on the effect of the aspect ratio and surface chemistry of the filler are also given.Glass transition of ultra-thin films of modified PVCY. Grohensa, , , J. Sacristanb, L.

19、Hamona, H. Reineckeb, C. Mijangosb and J.M. GuenetaUltra-thin layers (h=50150nm) of PVC, functionalised in solution by thiophenol (t-PVC) and 4-aminothiophenol (am-PVC), were prepared by spin-coating on silicon wafers. The glass transition temperature of these thin films was investigated by kinetic

20、scan ellipsometry. The Tg of the am-PVC and t-PVC modified PVC is found to increase more strongly with the degree of modification in thin layer geometry than in the bulk. Also, Tg(h) of t-PVC exhibits a larger increase in the confined state as compared to am-PVC. This result is unexpected since no s

21、pecific interactions are assumed between thiophenyl group and the surface indicating that other driving forces for the alteration of Tg(h) should be taken into account.In a second step, the supported PVC thin films are chemically cross-linked in solution by terephthaloyl chloride. The Tg(h) of the p

22、olymer layer increases with the cross-linking time more severely at a higher degree of modification but independently of the thickness of the layer indicating that the diffusion process is not altered in thin layers. Above Tg, the thermal expansion coefficient of the thin films is not modified after

23、 cross-linking, whereas, it was found to decrease strongly between 4 and 8% of modification in the uncured state.Keywords: Glass transition; PVC; Terephthaloyl chlorideBall Mill-Assisted Dechlorination of Flexible and Rigid Poly(vinyl chloride) in NaOH/EG SolutionTomohito Kameda, Masahiko Ono, Guido

24、 Grause, Tadaaki Mizoguchi and Toshiaki Yoshioka*Ind. Eng. Chem. Res., 2008, 47 (22), pp 86198624Both flexible and rigid forms of poly(vinyl chloride) (PVC) were effectively dechlorinated in NaOH/ethylene glycol (EG) solution during ball mill pulverization. The high degree of dechlorination obtained

25、 was attributed to the increased surface area of the crushed PVC particles and the resulting enhancement of contact between the PVC and dissolved hydroxide ions. The common additives diisononyl phthalate and CaCO3 were easily separated from the PVC bulk during the dechlorination reaction. The reacti

26、on proceeded under chemical control, with degrees of dechlorination for both flexible and rigid PVC increasing with temperature with apparent activation energies of 110 and 80 kJ/mol, respectively. This reaction was accurately represented by a modified shrinking-core model.Effects of artificial and

27、natural ageing on impact-modified poly(vinyl chloride) (PVC) References and further reading may be available for this article. To view references and further reading you must purchase this article.Ignacy Jakubowicz, a, In order to establish a correlation between results of natural and artificial tes

28、ts, a weathering programme for periods up to 12 years of natural ageing in Bors, Sweden was carried out using several impact-modified commercial poly(vinyl chloride) (PVC) materials. The artificial tests were performed in a Weather-O-Meter instrument equipped with a xenon arc as the light source. So

29、me tests were performed in accordance with ISO 4892 Part 2 and some tests using specially designed weathering cycles. The effects of ageing were monitored using measurements of impact strength and colour change. No significant correlation was found between results of the artificial and natural agein

30、g. The effect of temperature on the rate of degradation was evaluated in weathering cycles at different temperatures. The results were used to calculate activation energy, and gave a value of 11.2 kJ/mol for a Ca/Zn-stabilised material and 29.1 kJ/mol for other materials containing a mixture of Ba/C

31、d and Pb stabilisers or pure Pb stabiliser.Polymer Testing Volume 20 ,issue 5,2001,pages545-551Densities and Viscosities of Binary Mixtures of Poly(vinyl chloride) and Tetrahydrofuran at Temperatures (283.15 to 303.15) KM. Mohsen-Nia*, H. Modarress and F. AlimohammadyJ. Chem. Eng. Data, 2009, 54 (4)

32、, pp 13751377Viscosities and densities of poly(vinyl chloride) + tetrahydrofuran (PVC/THF) mixtures were measured at several temperatures between (283.15 and 303.15) K. The measured densities were satisfactorily correlated by a simple first-order polynomial with respect to PVC concentration. The ave

33、rage molecular weight of PVC is determined by measuring the specific viscosity of the PVC/THF mixtures. The obtained viscosity results are correlated by a new modified Eyrings viscosity model. The adjustment parameters are determined and presented. The comparison of correlated and experimental resul

34、ts indicated the applicability of the proposed model for viscosity prediction of (PVC/THF) mixturesElectrical conductivity studies of swift heavy ion modified PVC and PVCPANI composite Alok Srivastavaa, c, , , Virendra Singha, Amita Chandrab, K. Wittec, U.W. Schererc and T.V. SinghaThe physico-chemi

35、cal changes brought about by swift heavy ions of silicon and nickel in polyvinyl chloride (PVC) are discussed in terms of optical, electrical and chemical modifications. The electrical conductivity of the polyvinyl chloride, both in independent form as well as in blended form, increases with the inc

36、rease in the ion fluence and the mass of the swift heavy ions. It was further observed that under the present experimental conditions, PVC did not have any significant influence on the electrical conductivity of PVCPANI blend. The present work shows that swift heavy ion modification technique under

37、limited conditions could be utilized for increasing the conductivity of insulating polymer conducting polymer (IPCP) blends.Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and AtomsVolume 245, Issue 1, April 2006, Pages 277-280Effect of physical aging

38、on the gas transport properties of PVC and PVC modified with pyridine groups Purchase$ 39.95References and further reading may be available for this article. To view references and further reading you must purchase this article.P. Tiemblo, a, , J. Guzmna, E. Riandea, C. Mijangosa and H. ReineckeaThe

39、 gas transport coefficients of polyvinyl chloride (PVC) and PVC modified with pyridine groups have been studied. It has been observed that there is a strong time dependence of the permeability and diffusivity of oxygen, nitrogen, carbon dioxide and methane in membranes prepared by solvent casting of

40、 PVC and pyridine modified PVC. For PVC there is a two-fold reduction of the diffusion coefficients during the first two days, and about one order of magnitude, a month after the membranes are prepared, and no stabilisation of the trend is seen after a month. Membranes prepared from modified PVC sho

41、w a short-term diffusion rate reduction which is similar to that found in PVC, while at longer times the diffusion rate decrease levels off quickly, attaining constant values after about ten days. The time dependence of the transport coefficients is attributed to the samples physical aging and an at

42、tempt is made to fit the experimental data by considering a stretched exponential time dependence of the volume contraction on aging.Polymer, Volume 42, Issue 19, September 2001, Page 8321,Tween 20-modified poly(vinyl chloride) exhibits enhanced blood-compatibility1. Biji Balakrishnan, 2. Nirmala R

43、James, 3. A JayakrishnanPoly(vinyl chloride) (PVC) resin was modified by grafting the non-ionic surfactant poly(oxyethylene 20 sorbitan) monolaurate (Tween 20) using isocyanate chemistry. PVC was aminated using ethylenediamine and coupled with hexamethylene diisocyanate. Tween 20 was then reacted wi

44、th the polymer, resulting in the grafting of the surfactant. The polymer modification was confirmed using infrared and X-ray photo-electron spectroscopy. Films of modified polymer were cast from a solution of tetrahydrofuran. The surface of films prepared from the modified polymer showed increased h

45、ydrophilicity as evidenced by contact-angle measurements. The solid/water free energy of the modified polymer surface was nearly a quarter of the energy of the bare PVC surface. Static platelet adhesion studies using platelet-rich plasma demonstrated significantly reduced adhesion onto a modified PV

46、C surface compared with unmodified PVC. Data obtained demonstrate that modification of polymers with Tween 20 may be an interesting way of imparting protein- and cell-repelling characteristics to them, thereby improving their blood-compatibility. Copyright 2005 Society of Chemical IndustryPolymer In

47、ternationalVolume54,Issue9,Pages1304-1309,September2005Small-angle X-ray scattering study of modified porous suspensionpoly(vinyl chloride) particles1. M. Shach-Caplan, 2. Y. Haba, 3. M. Narkis, 4. Y. Cohen, 5. H. Bianco-PeledSmall-angle X-ray scattering (SAXS) was applied to investigate the microst

48、ructure of unmodified and modified porous commercial suspension-type poly(vinyl chloride) (PVC) particles. The modified PVC particles were prepared by an in situ stabilizer-free polymerization/crosslinking of particles absorbed with a monomer/crosslinker/peroxide solution. The modifying polymers inc

49、lude styrene with or without divinyl benzene (DVB) as a crosslinker and methyl methacrylate (MMA) with or without ethylene glycol dimethacrylate (EGDMA) as a crosslinker. The SAXS method was used to highlight the effect of polystyrene (PS) on the microstructure of PVC particles and to evaluate the c

50、haracteristic lengths, both in the PVC/PS and the PVC/XPS (PS crosslinked with 0 and 5% DVB, respectively) systems. A model is suggested, where during the synthesis modification process, swelling of PVC by styrene and styrene polymerization occur simultaneously. PVC swelling by styrene causes destruction of the PVC subprimary particles, whereas styrene polymerization leads